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1.
Sci Justice ; 63(1): 1-8, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36631174

RESUMO

Geophysical investigation of a former convent graveyard for conversion to a community centre identified an unrecorded, unmarked burial below a later burial. Archaeological excavation confirmed the presence of skeletonized human remains, considered by police as a possible clandestine burial. Mortuary examination indicated the remains belonged to a mature adult female. To determine whether the deceased could be a recorded missing person, radiocarbon dating was undertaken on a femur and a rib bone. This is not always straightforward, and results showed two possible ages due to intercepts on either side of the nuclear weapons testing spike in atmospheric 14C; however, the later dated burial allowed us to constrain the date of a rib to CE 1959. This study demonstrates that dating a second tissue with a longer turnaround time, such as a femur, can help to constrain which side of the bomb spike is most probable. This paper documents in one work the search, scene and sample and then advances this to resolution by anthropological analysis and radiocarbon dating of human remains.


Assuntos
Cemitérios , Antropologia Forense , Adulto , Humanos , Feminino , Antropologia Forense/métodos , Irlanda , Datação Radiométrica , Restos Mortais , Sepultamento
2.
Sci Rep ; 12(1): 11374, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35790842

RESUMO

Mid-latitude alpine caves preserve a record of past solid precipitation during winter, locally spanning several centuries to millennia. Dating organic macro-remains trapped in ice layers allows the determination of timing and duration of past periods of positive and negative ice mass balance. We present here the largest comparative study of ice cave sites yet published, using Bayesian age-modelling on a database comprising 107 radiocarbon dates, spread over eight caves in the Austrian Alps. We show that periods of positive mass balance coincide with past glacier advances. We find organic and macro-remain rich layers dated to the Medieval Climate Anomaly (between 850 and 1200 CE) marking widespread ice retreat. We demonstrate positive ice mass balance at all studied sites for the Little Ice Age, coinciding with the largest glacier advances in the Holocene between 1400 and 1850 CE. At the sites with records spanning over 2000 years, positive mass balance is also observed during the periods from 300 BCE to 100 CE and 600-800 CE. These subterranean ice deposits show widespread evidence of accelerated negative mass balances in recent years and their record is under imminent threat of disappearing.


Assuntos
Clima , Camada de Gelo , Áustria , Teorema de Bayes , Estações do Ano
3.
Proc Natl Acad Sci U S A ; 117(35): 21005-21007, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817536

RESUMO

The new radiocarbon calibration curve (IntCal20) allows us to calculate the gradient of the relationship between 14C age and calendar age over the past 55 millennia before the present (55 ka BP). The new gradient curve exhibits a prolonged and prominent maximum between 48 and 40 ka BP during which the radiocarbon clock runs almost twice as fast as it should. This radiocarbon time dilation is due to the increase in the atmospheric 14C/12C ratio caused by the 14C production rise linked to the transition into the Laschamp geomagnetic excursion centered around 41 ka BP. The major maximum in the gradient from 48 to 40 ka BP is a new feature of the IntCal20 calibration curve, with far-reaching impacts for scientific communities, such as prehistory and paleoclimatology, relying on accurate ages in this time range. To illustrate, we consider the duration of the overlap between Neanderthals and Homo sapiens in Eurasia.


Assuntos
Paleontologia/métodos , Datação Radiométrica/métodos , Animais , Calibragem/normas , Fósseis , Humanos , Homem de Neandertal
4.
J Hum Evol ; 114: 35-44, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29447760

RESUMO

Africa's southern Cape is a key region for the evolution of our species, with early symbolic systems, marine faunal exploitation, and episodic production of microlithic stone tools taken as evidence for the appearance of distinctively complex human behavior. However, the temporally discontinuous nature of this evidence precludes ready assumptions of intrinsic adaptive benefit, and has encouraged diverse explanations for the occurrence of these behaviors, in terms of regional demographic, social and ecological conditions. Here, we present a new high-resolution multi-proxy record of environmental change that indicates that faunal exploitation patterns and lithic technologies track climatic variation across the last 22,300 years in the southern Cape. Conditions during the Last Glacial Maximum and deglaciation were humid, and zooarchaeological data indicate high foraging returns. By contrast, the Holocene is characterized by much drier conditions and a degraded resource base. Critically, we demonstrate that systems for technological delivery - or provisioning - were responsive to changing humidity and environmental productivity. However, in contrast to prevailing models, bladelet-rich microlithic technologies were deployed under conditions of high foraging returns and abandoned in response to increased aridity and less productive subsistence environments. This suggests that posited links between microlithic technologies and subsistence risk are not universal, and the behavioral sophistication of human populations is reflected in their adaptive flexibility rather than in the use of specific technological systems.


Assuntos
Adaptação Biológica , Arqueologia , Clima , Animais , Humanos , África do Sul , Tecnologia
5.
Quat Sci Rev ; 68(100): 17-42, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23805019

RESUMO

Drill cores from the inner-alpine valley terrace of Unterangerberg, located in the Eastern Alps of Austria, offer first insights into a Pleistocene sedimentary record that was not accessible so far. The succession comprises diamict, gravel, sand, lignite and thick, fine grained sediments. Additionally, cataclastic deposits originating from two paleo-landslide events are present. Multi-proxy analyses including sedimentological and palynological investigations as well as radiocarbon and luminescence data record the onset of the last glacial period (Würmian) at Unterangerberg at ∼120-110 ka. This first time period, correlated to the MIS 5d, was characterised by strong fluvial aggradation under cold climatic conditions, with only sparse vegetation cover. Furthermore, two large and quasi-synchronous landslide events occurred during this time interval. No record of the first Early Würmian interstadial (MIS 5c) is preserved. During the second Early Würmian interstadial (MIS 5a), the local vegetation was characterised by a boreal forest dominated by Picea, with few thermophilous elements. The subsequent collapse of the vegetation is recorded by sediments dated to ∼70-60 ka (i.e. MIS 4), with very low pollen concentrations and the potential presence of permafrost. Climatic conditions improved again between ∼55 and 45 ka (MIS 3) and cold-adapted trees re-appeared during interstadials, forming an open forest vegetation. MIS 3 stadials were shorter and less severe than the MIS 4 at Unterangerberg, and vegetation during these cold phases was mainly composed of shrubs, herbs and grasses, similar to what is known from today's alpine timberline. The Unterangerberg record ended at ∼45 ka and/or was truncated by ice during the Last Glacial Maximum.

7.
Science ; 307(5708): 362-4, 2005 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-15661996
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